1. Field of the Invention
The present invention relates to an electronic apparatus with a built-in CPU (Central Processing Unit). More particularly, the invention relates to an electronic apparatus with a built-in CPU that has a cooling structure for cooling the inside of the apparatus by effectively removing or dissipating the heat generated by the CPU.
2. Description of the Related Art
Conventionally, with an electronic information processing system or apparatus such as a personal computer, at least one cooling fan is mounted along with at least one built-in CPU. This is to discharge effectively the heat generated by the CPU to the outside of the casing. To meet this need, various techniques have been developed. Examples of these techniques are disclosed by the Japanese Non-Examined Patent Publication Nos. 10-93274 and 10-124179 both published in 1998, and the Japanese Patent No. 2577731 published in 1996 (which corresponds to the Japanese Non-Examined Patent Publication No. 63-173111 published in 1988).
The Publication No. 10-93274 discloses the cooling structure of information processing apparatuses or systems (e.g., personal computers) that increases the cooling efficiency while suppressing the noise caused by the cooling fan or fans. In this structure, a partition is provided in the casing having an air inlet and an air outlet, thereby forming a room to surround a cooling fan and heat generators (e.g., CPUs) mounted in the casing. The fan and the heat generators are almost separated by the partition from the other electronic units or devices mounted in the casing. The room is formed to communicate with the air inlet of the casing. The partition has an opening for allowing the flowing air generated by the cooling fan in the room to go out of the room. An air path is formed in the casing in such a way as to interconnect the opening of the partition with the air outlet of the casing. The air path is like a spiral while the opening of the partition is set as the spiral center.
With the cooling structure of the Publication No. 10-93274, the flowing air generated by the cooling fan in the room, which includes heat generated by the heat generators, will be emitted to the outside of the room through the opening of the partition. Thereafter, the flowing air will pass through the air path to the air outlet of the casing and then, it will go out of the casing through the air outlet. Preferably, the cooling fan is formed by a centrifugal fan.
The Publication No. 10-124179 discloses an information processing apparatus (e.g., a personal computer) with a cooling structure that improves the cooling efficiency. In this structure, a flexible disk drive (FDD) unit and a compact disk read-only memory (CD-ROM) unit are mounted in the casing in such a way as to be entirely overlapped with each other in their horizontal state. A hard disk drive (HDD) unit is mounted in its vertical state to be adjacent to the FDD and the CD-ROM units in the casing. A power supply unit is mounted in the rear of the FDD, CD-ROM, and HD units in the casing. Thus, a considerably wide space is formed near the power supply unit in the casing.
A set of air inlets is only formed at the left-side wall of the casing near its front wall. An air flow is generated by the fan built in the power supply unit so as to extend from the set of air inlets to a set of air outlets formed at the rear wall of the casing. The air flow thus formed in the casing is like an L character. The flowing air will pass by not only the HDD unit but also the FDD and CD-ROM units, thereby cooling efficiently these units while suppressing the cooling noise.
With the cooling structure of the Publication No. 10-124179, the HDD, FDD, and CD-ROM units can be mounted on the right side in the casing near its front wall with the use of an appropriate mounting member. Thereafter, the power supply unit wider than the CD-ROM unit can be mounted in the casing. Moreover, the HDD, FDD and CD-ROM units and the power supply unit can be efficiently cooled by the air introduced into the casing through the set of air inlets.
The U.S. Pat. No. 2,577,731 discloses a personal computer with a cooling structure that makes it possible to cool efficiently the inside of the computer with a single cooling fan and that decreases the noise and cost. In this computer, a disk unit a power supply unit, a cooling fan, and a circuit unit are mounted in a casing. The disk unit, which is placed near the front wall of the casing, is designed in such a way that the air enters the inside of the unit and penetrates through the same. The power supply unit, which is placed in rear of the disk unit, is designed in such a way that the air enters the inside of the unit and penetrates through the same.
The casing comprises an attachment plate for dividing the inner space or the casing into an upper first room and a lower second room, and a set of air inlets for introducing the outside air into the first and second rooms. The disk unit and the power supply unit are placed in the first room while the circuit unit is placed in the second room.
The cooling fan discharges the inside air in the second room to the outside of the casing. At the same time, the fan discharges the inside air in the first room, which is introduced through the opening of the disk unit and the set of air inlets, to the outside of the casing by way of the inside of the power supply unit. Thus, the air introduced through the disk unit passes through the power supply unit, thereby improving the cooling efficiency.
With the computer of the U.S. Pat. No. 2,577,731 due to the blowing action of the cooling fan, the power supply unit and the disk-unit placed in the first room can be cooled and at the same time, the circuit unit placed in the second room can be cooled. Therefore, the inside of the casing can effectively be cooled with the single cooling fan. This means that satisfactory cooling effect is realized with a single cooling fan and thus, cooling noise and fabrication cost are lowered.
In recent years, the mounting density of electronic devices and/or units in the casing has been progressing and at the same time, the heat mount generated in the casing has been increasing steadily with the improving performance or the CPU. Therefore, it has become considerably difficult to discharge efficiently the heat generated in the casing to the outside. In other words, there is an increasing danger that some of the heat generated by the CPU tends to be confined in the casing and as a result, the confined heat will apply bad effects to the other electronic devices and/or units mounted in the casing. In the near future, the above-described trend will be promoted more and accordingly, there will arise a serious problem how the heat generated by the CPU is efficiently discharged from the casing, in other words, how to cool the inside of the casing effectively.
With the above-described technique disclosed by the Publication No. 10-93274, the CPU is almost separated by the partition from the other electronic units or devices in the casing in such as way that a spiral-shaped flow of air is formed in the casing. Therefore, the heat generated by the CPU is circulated by the air flow in the entire casing and then, discharged to the outside from the casing. As a result, there is a problem that the heat generated by the CPU tends to apply a bad effect to the other electronic units or devices, such as the HDD and FDD units, mounted in the casing.
With the above-described techniques disclosed by the Publication No. 10-124179 and the U.S. Pat. No. 2,577,731, the heat generated by the CPU is circulated by the air flow in the entire casing and then, discharged to the outside from the casing. As a result, the same problem as the Publication No. 10-93274 will occur.
Accordingly, an object of the present invention is to provide an electronic apparatus that prevents other electronic devices/units mounted in a casing along with a built-in CPU from being badly affected by the heat generated by the CPU even if the mounting density of electronic devices and/or units in the casing progresses and the heat amount generated by the CPU increases.
Another object of the present invention is to provide an electronic apparatus that dissipates more efficiently the heat generated by a built-in CPU from the casing with a simple measure.
The above objects together with others not specifically mentioned will become clear to those skilled in the art from the following description.
An electronic apparatus according to the invention comprises:
(a) a casing hating a first air inlet and a first air outlet;
(b) at least one electronic device/unit mounted in the casing;
(c) a CPU mounted in the casing;
the CPU cooperating with the at least one electronic device/unit to realize desired functions;
the CPU having a first fan for cooling the same; and
(d) a partition fixed in the casing in such a way as to form a first room and a second room;
the CPU and the first fan being placed in the first room:
the at least one electronic device/unit being placed in the second room;
wherein the air is introduced into the first room through the first air inlet with an operation of the first fan and then, discharged from the first room through the first air outlet without contacting the least one electronic device/unit.
With the electronic apparatus according to the inventions the casing has the first air inlet and the first air outlet. The CPU mounted in the casing has the first fan for cooling the CPU itself. The partition is fixed in the casing in such a way as to form the first room and the second room. The CPU and the first fan are placed in the first room while the at least one electronic device/unit is placed in the second room. The air is introduced into the first room of the casing through the first air inlet with the operation of the first tan and then, discharged from the first room through the first air outlet without contacting the least one electronic device/units.
As result, even if the mounting density of the electronic devices and/or units in the casing progresses and the heat amount generated by the CPU increased, the at least one electronic device/unit is prevented from being badly affected by the heat generated by the built-in CPU.
Moreover, the air including the heat generated by the built-in CPU in the first room does not contact the least one electronic device/unit in the second room. The air in the first room is immediately discharged from the first room through the first air outlet. As a result, the heat generated by the CPU is dissipated more efficiently from the casing with a simple measure of fixing the partition in the casing.
In a preferred embodiment of the apparatus according to the invention, a duct is additionally provided to interconnect the first fan for the CPU with the first air inlet in the first room. In this embodiment, there is an additional advantage that the cooling effect for the CPU is enhanced.
In another preferred embodiment of the apparatus according to the invention, the partition has a heat-insulating property. For example, the partition is made of a heat-insulating material, or the partition is covered with a heat-insulating member or material. In this embodiment, there is an additional advantage that the effect of the heat generated by the CPU in the first roam to the at least one electronic device/unit in the second room can be shielded or blocked almost completely.
In still another preferred embodiment of the apparatus according to the invention, a second air inlet formed at the casing in the second room, a second air outlet formed at the casing in the second room to be opposite to the second air inlet, and a second fan mounted to race the second air outlet in the second room are additionally provided. The second air inlet is used to introduce the air into the second room. The second air outlet is used to discharge the air introduced into the second room to the outside of the casing in such a away as to contact the least one electronic device/unit. In this embodiment, there is an additional advantage that the least one electronic device/unit in the second room is cooled efficiently by the air flowing through the second room from the second air inlet to the second air outlet.